(Topic ID: 58326)

Coil Testing Help Needed - *Fixed*

By mkgort

10 years ago


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Topic Stats

  • 14 posts
  • 4 Pinsiders participating
  • Latest reply 10 years ago by mkgort
  • Topic is favorited by 1 Pinsider

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#1 10 years ago

I am working on a WWF that is having problems with the back panel diverter. The previous owner had accidentally shorted the two wires coming into the 32-1800 coil. This, of course, caused multiple problems upstream. Transistors and fuses were replaced, but still no luck with the diverter. I suspect the coil is toast, but I want to make sure.

I am getting voltage to only one lug, which I have read is a good sign the coil is bad. But, why does the coil ohm out correctly? I get 51 ohms (proper for this coil).

Is this contradictory?

Thanks!

-MK

#3 10 years ago

Thanks for the input.

Just did the test. The coil did not fire. Also traced both wires back to the board and have continuity on both.

-MK

#5 10 years ago

I would agree. But, is it normal for a bad coil to ohm out to spec?

-MK

#7 10 years ago

Thank you for the info!

I think it's time to go shopping

-MK

#9 10 years ago

Hi Robert. I did both tests just to be sure. Grounded the transistor tab, and grounded the non-banded lug. No joy. I have measured the coil in and out of the game, with and without the diode (even with and without the wires soldered on). The driver and pre-driver were replaced (Tip 102 for the tip122). All other coils and flashers are functional.

Thanks!

-MK

#11 10 years ago

Thank you all for the input.

I replaced the coil, transistor, and pre-driver, they all tested OK with the MM. I assume at this point I should be looking at the 7408?

I appreciate any thoughts.

-MK

#13 10 years ago
Quoted from robertmee:

After you replaced them all, are you able to get the coil to fire by grounding the transistor?

I completely forgot to mention: now the coil just locks on. I've got the board pulled and I'm going to recheck my work and may just re-replace the transistor and see what happens.

Thanks!

-MK

#14 10 years ago

Replaced the 7408 and all is well!

Thank you for the input.

-MK

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